This invention relates to a motor-driven compressor adapted for use in a vehicle and provided with built-in inverter circuit and filter circuit.
As a refrigerant gas compressor used in a vehicle air conditioner, a motor-driven compressor has been known. In the housing of such motor-driven compressor, a compressor mechanism for compressing refrigerant gas, an electric motor for driving the compressor, an inverter circuit for controlling the driving power for the electric motor, and a filter circuit for removing the noise of input power for the inverter are accommodated. The inverter circuit and the filter circuit are usually housed in the same accommodation chamber formed in the compressor housing.
The filter circuit of the motor-driven compressor includes a capacitor and a coil of a relatively large size. The size of the filter circuit affects the designing of the shape or the size of an accommodation chamber in the housing and hence the outer shape of the motor-driven compressors. Additionally, any change of the outer shape affects the ease of mounting of the compressor to a vehicle. Therefore, it is hard to secure a space for an accommodation chamber having a required shape and size.
Japanese Unexamined Patent Application Publication No. 2011-32893 discloses a housing for motor-driven compressors for a vehicle which has formed therein a chambers for the inverter circuit and the filter circuit, respectively. Additionally, Japanese Unexamined Patent Application Publication No. 2002-188574 discloses a housing for motor-driven compressor for a vehicle which has formed therein a chamber for accommodating the capacitor of a filter circuit.
Therefore, arrangement of a chamber for accommodating the entire of a filter circuit or any component of the filter circuit separately from an accommodation chamber for an inverter circuit makes possible securing an accommodating space for the filter circuit while reducing the change of the outer shape of the compressor.
However, the provision of two separate chambers affects the ease of assembling of the inverter circuit and the filter circuit. Especially, the connection between the power cable for the motor-driven compressors and the input terminal of the filter circuit and the connection between the output terminal of the filter circuit and the inverter circuit need to be performed from opposite directions, which complicates the assembly of the filter circuit.
The present invention which has been made in light of the above problems is directed to a motor-driven compressor for a vehicle which is easy to provide accommodating space for the filter circuit and to assemble the filter circuit.